During mid-development of Batman and Walking Dead Season 3,  an artist requested the ability to strip out alpha from textures without having to necessarily open it up in Photoshop. As it turned out, she noticed that Substance Painter had been exporting images with an alpha channel, regardless of whether or not it was using it. While this has been fixed in more recent releases of Painter, I ended up using part of the script to basically get a better understanding of how assets were being generated by the art department. Keeping track of it helped get ‘easy wins’ when it came down to optimizations, as having an alpha channel in a texture that wasn’t being used just took up more memory.

There are a number of image manipulation / operation modules available for Python – but I found PIL ( https://pypi.python.org/pypi/PIL ) to be fairly straight forward to use when analyzing targas – the texture format of choice at Telltale. Below is a snippet of how easy it is to find textures with an alpha channel and strip them out. At Telltale I ended up passing the file-list to a QListWidget and connected a QPushButton to a function to re-save.

for tga in fileList[:]:
			
			print ("Processing {0}").format(tga)
		 	TGA = Image.open(tga)
		 	if TGA.mode == 'RGBA':
		 		print ("Found Alpha channel")
		 		try:
		 			TGA = TGA.convert('RGB')
		 			TGA.save (tga)
		 			print ("Successfully saved without alpha")
		 		except IOError as e:
		 			print ("Couldn't save - please make sure the file is checked out")
		 		finally: 
		 			pass

Looking at this old code I noticed I unnecessarily use fileList[:]  instead of just fileList . I’m not sure why I used to do this, but it’s definitely not something I do anymore.

A full list of image modes can be found on the PIL docs here: http://effbot.org/imagingbook/concepts.htm#mode , but as a tech artist in games you’ll probably run into L, RGB and RGBA the most.